This invention relates to an information recording method, an information recording device, an information reproducing device, and an information storage medium which are suitable for recording various types of information, including video information and/or audio information, and further computer data, onto a recording medium.
In the information recording method and device, various types of information are recorded continuously onto an information storage medium without logical intermission. In the information storage medium, the recorded information includes information about a data structure that enables the recorded information to be managed effectively and reproduced continuously.
There are laser disks (LDs) and digital video (DVD) disks used as information storage mediums on which video information or audio information has been recorded. The information storage mediums, however, are only for playback use and have no defective area thereon.
There are DVD-RAM disks used as mediums for storing computer information. This type of medium enables additional recording. In addition, a method of replacing a defective area occurring on the information storage medium has been established.
One known method of replacing a defective area occurring in recording computer information on a RAM disk is a linear replacement process.
This process is a method of, when a defect has occurred, securing a replacement area in a spare area secured in another area physically separate from a user area and setting a logical block number (LBN) in the replacement area. In this method, when a defective area has occurred in the middle of recording or reproducing information onto or from a disk, the optical head has to record the data in the spare area in a physically separate position and thereafter return to the position where it interrupted the recording and resume recording the subsequent data. This results in the frequent movement of the optical head.
In the computer system, the control hierarchy is divided into a video recording and reproducing application software (hereinafter, abbreviated as recording/reproducing application) layer, a file system layer, and an optical disk drive (ODD) layer in the section for processing information and recording and reproducing information.
Commands acting as interfaces have been defined between the layers. Addresses dealt with at each layer differ from one level of hierarchy to another.
Specifically, the recording/reproducing application layer deals with audio and video addresses (commonly known as AV addresses), the file system layer deals with logical sector numbers (LSN) or logical block numbers (LBN) on the basis of AV addresses, and the optical disk drive layer deals with physical sector numbers (PSN) on the basis of logical sector numbers (LSN) or logical block numbers (LBN).
Now, consider a case where video information or audio information according to the recording format of a DVD video disk is recorded on a DVD-RAM disk. As described above, when the linear replacement process is performed as a method of processing (replacing) a defect, each time a defective ECC block is encountered in recording, the head has to move back and fourth between the user area explained later and the spare area.
Such frequent access of the optical head in recording permits the amount of video information stored in the buffer memory to exceed the memory capacity because of the transfer speed and data amount of the input data, the access time in recording, the buffer memory capacity, and others, which makes continuous recording impossible.
Although it is hoped that video information to be recorded is managed in the video recording and reproducing application software layer without the burden of managing defects on the information storage medium, if many defective areas have occurred on the information storage medium, a conventional method permits the influence of defects in the information storage medium to extend even to the video recording and reproducing application software layer, which makes stable video information management difficult.
Furthermore, in the case of recordable and reproducible disks, there has been a desire that they should be used for not only AV data but also various types of information recording.
(1) It is, accordingly, an object of the present invention to provide an information recording method, an information recording device, an information reproducing device, and an information storage medium which have specific recording units set therein and enable environmental setting to achieve stable video information management (specifically, a video information recording, reproducing, and editing method in a system) even if a defective area or another data area exists in the specific recording units. According to the present invention, there are also provided an information recording device and an information reproducing device which have a most suitable system for realizing the above environment.
(2) Another object of the present invention is to provide an information recording method, an information recording device, an information reproducing device, and an information storage medium which improve the method of managing AV file identification information to make it easier to identify and manage different types of data.
(3) Another object of the present invention is to provide an information recording method, an information recording device, an information reproducing device, and an information storage medium which maintain the boundary between specific data block units (for example, ECC units) using unused extents, thereby facilitating the error correction management of data and the additional recording process and management of subsequent data, when AV data is recorded.
(4) Another object of the present invention is to provide an information recording method, an information recording device, an information reproducing device, and an information storage medium which not only search in advance for a place where AV data is to be recorded to prevent data from being recorded in another data area or a defective area, but also have the function of securing a recording area to prevent errors in recording.
(5) Another object of the present invention is to provide an information recording method, an information recording device, an information reproducing device, and an information storage medium which always write data in, for example, error correction codes (ECC) block units in recording data in such a manner that they perform reading control at the beginning of writing, search for the recorded state of the error correction codes, and write data while maintaining the block units of the error correction codes, thereby improving the data writing efficiency and assuring the reliability of the error correcting process of data.
(6) Another object of the present invention is to provide an information recording method, an information recording device, an information reproducing device, and an information storage medium which are additionally provided with a file partial delete command, thereby enabling editing to be done more easily.
The foregoing objects are accomplished as follows:
In accordance with one aspect of the present invention, there is provided an information recording method for recording information on an information storage medium which has a logical structure in which (i) an AV file is provided to store audio data or video data, (ii) defective area management information is provided as information containing information of a defective area, (iii) file management information is provided to manage at least the AV file and file entry information, the file entry information including at least one allocation descriptor of extents for data allocation, and (iv) a contiguous data area (CDA) is provided, wherein the contiguous data area serves as a unit for setting data allocation, and permits skipping to be performed. The contiguous data area has a size expressed by the following formula:
CDAxe2x89xa7STRxc3x97RTRxc3x97(Ta+Tskip+Tpc)/(RTRxe2x88x92STR)
wherein STR is an average transmission rate of a control section, RTR is a physical transmission rate, Ta is an average access time of accessing operations in each of which reading means accesses a recording area on an information storage medium, Tskip is time required for recording in the contiguous data area, and Tpc is time required for skipping other existing files and defective areas subjected to a linear replacement process or skipping replacement process. The information recording method includes the steps of searching for an unrecorded area on the information storage medium; setting an area to be recorded in the unrecorded area based on the contiguous data area; setting extent portions in the area to be recorded, in such a manner as to avoid areas other than the AV file; and recording AV data. The data stored in areas other than the AV file is data of a personal computer (PC) file. The information recording medium is preferably configured to store the AV data and the file management information.
In accordance with another aspect of the invention, there is provided an information recording apparatus for recording information on an information storage medium which has a logical structure in which (i) an AV file is provided to store audio data or video data, (ii) defective area management information is provided as information containing information of a defective area, (iii) file management information is provided to manage at least the AV file and file entry information, the file entry information including at least one allocation descriptor of extents for data allocation, and (iv) a contiguous data area (CDA) is provided, wherein the contiguous data area serves as a unit for setting data allocation, and permits skipping to be performed, the contiguous data area has a size expressed by the following formula:
CDAxe2x89xa7STRxc3x97RTRxc3x97(Ta+Tskip+Tpc)/(RTRxe2x88x92STR)
where STR is an average transmission rate of a control section, RTR is a physical transmission rate, Ta is an average access time of accessing operations in each of which reading means accesses a recording area on the information storage medium, Tskip is time required for recording in the contiguous data area, and Tpc is time required for skipping other existing files and defective areas subjected to a linear replacement process or skipping replacement process. The information recording apparatus comprises means for searching for an unrecorded area on the information storage medium; means for setting an area to be recorded in the unrecorded area based on the contiguous data area; means for setting extent portions in the area to be recorded, in such a manner as to avoid areas other than the AV file; and means for recording AV data.
In accordance with yet another aspect of the invention, there is provided an information recording medium configured to record information based on (i) an AV file for storing audio data or video data, (ii) defective area management information containing information of a defective area, (iii) file management information for managing at least the AV file and file entry information, the file entry information including at least one allocation descriptor of extents for data allocation, and (iv) a contiguous data area (CDA), wherein the contiguous data area serves as a unit for setting data allocation, and permits skipping to be performed, the contiguous data area has a size expressed by the following formula:
CDAxe2x89xa7STIRxc3x97RTRxc3x97(Ta+Tskip+Tpc)/(RTRxe2x88x92STR)
where STR is an average transmission rate of a control section, RTR is a physical transmission rate, Ta is an average access time of accessing operations in each of which reading means accesses a recording area on the information storage medium, Tskip is time required for recording in the contiguous data area, and Tpc is time required for skipping other existing files and defective areas subjected to a linear replacement process or skipping replacement process.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.